Buggy code:
class NewModelControllerImpl implements NewModelController { private static final ModelNode EMPTY ; private final ServiceRegistry serviceRegistry ; private final ServiceTarget serviceTarget ; private final ModelNodeRegistration rootRegistration ; private final Lock writeLock = new ReentrantLock ( ) ; private final ContainerStateMonitor stateMonitor ; private final AtomicReference < ModelNode > modelReference = new AtomicReference < ModelNode > ( NewModelControllerImpl . EMPTY ) ; private final ConfigurationPersister persister ; private final Type controllerType ; private final AtomicBoolean bootingFlag = new AtomicBoolean ( true ) ; private final NewStepHandler prepareStep ; private final ControlledProcessState processState ; NewModelControllerImpl ( final ModelNode model , final ServiceRegistry serviceRegistry , final ServiceTarget serviceTarget , final ModelNodeRegistration rootRegistration , final ContainerStateMonitor stateMonitor , final ConfigurationPersister persister , final NewOperationContext . Type controllerType , final NewStepHandler prepareStep , final ControlledProcessState processState ) { } static final ThreadLocal < Boolean > RB_ON_RT_FAILURE = new ThreadLocal < Boolean > ( ) ; public ModelNode execute ( final ModelNode operation , final OperationMessageHandler handler , final OperationTransactionControl control , final OperationAttachments attachments ) { } void boot ( final List < ModelNode > bootList , final OperationMessageHandler handler , final OperationTransactionControl control ) { } ModelNodeRegistration getRootRegistration ( ) { } private static void reportNoHandler ( final String operationName , final PathAddress address , final ModelNode response ) { } class BootStepHandler implements NewStepHandler { private final ModelNode operation ; private final ModelNode response ; BootStepHandler ( final ModelNode operation , final ModelNode response ) { } public void execute ( final NewOperationContext context , final ModelNode operation ) throws OperationFailedException { final PathAddress address = PathAddress . pathAddress ( operation . require ( ADDRESS ) ) ; NewStepHandler stepHandler = rootRegistration . getOperationHandler ( address , operation . require ( OP ) . asString ( ) ) ; if ( stepHandler == null ) { <START_BUG> throw new OperationFailedException ( new ModelNode ( ) . set ( ( "No<seq2seq4repair_space>handler<seq2seq4repair_space>for<seq2seq4repair_space>operation<seq2seq4repair_space>address<seq2seq4repair_space>" + address ) ) ) ; <END_BUG> } else { NewOperationContext . Stage stage = Stage . MODEL ; if ( stepHandler instanceof AbstractExtensionAddHandler ) { stage = Stage . IMMEDIATE ; } context . addStep ( response , this . operation , stepHandler , stage ) ; } context . completeStep ( ) ; } } public NewModelControllerClient createClient ( final Executor executor ) { } void writeModel ( ModelNode newModel ) throws ConfigurationPersistenceException { } void acquireLock ( final boolean interruptibly ) throws InterruptedException { } void releaseLock ( ) { } void acquireContainerMonitor ( ) { } void releaseContainerMonitor ( ) { } void awaitContainerMonitor ( final boolean interruptibly , final int count ) throws InterruptedException { } ServiceRegistry getServiceRegistry ( ) { } ServiceTarget getServiceTarget ( ) { } State getState ( ) { } Object setReloadRequired ( ) { } Object setRestartRequired ( ) { } void revertReloadRequired ( Object stamp ) { } void revertRestartRequired ( Object stamp ) { } }

Fix:
context . getFailureDescription ( ) . set ( new ModelNode ( ) . set ( ( "No<seq2seq4repair_space>handler<seq2seq4repair_space>for<seq2seq4repair_space>operation<seq2seq4repair_space>address<seq2seq4repair_space>" + address ) ) ) ;